Five year plans have been put into operation to mitigate the sufferings of the poor.

Answer: Option A

Lessen : make or become less; diminish.
Remove : take (something) away or off from the position occupied.
Reduce : make smaller or less in amount, degree, or size.
Cut : make an opening, incision, or wound in (something) with a sharp-edged tool or object.
Mitigate : make (something bad) less severe, serious, or painful.

Synonym of Mitigate is Lessen